Explanation: The River Hugli, a distributary of the Ganges, is a significant waterway in West Bengal, particularly in the city of Kolkata. It serves as a vital link for transportation and commerce, and several bridges have been constructed to facilitate movement across the river. Among these, the Howrah Bridge and the Vidyasagar Setu are two of the most prominent.
The Howrah Bridge, also known as the Rabindra Setu, is one of the most recognizable landmarks in Kolkata. It is a cantilever bridge that connects the city of Kolkata with the suburb of Howrah. The bridge was completed in 1943 and is known for its unique design and engineering. It is a critical link for both vehicular and pedestrian traffic, serving millions of people daily.
The Vidyasagar Setu, also referred to as the Second Hooghly Bridge, is a cable-stayed bridge that was completed in 1992. It is located downstream from the Howrah Bridge and serves as a major transportation artery, reducing the traffic burden on the older Howrah Bridge. The Vidyasagar Setu is named after the renowned Bengali polymath Ishwar Chandra Vidyasagar.
Both these bridges are significant not only for their functional roles but also for their historical and cultural importance. They are symbols of Kolkata's development and engineering prowess. The Mahatma Gandhi Setu, on the other hand, is a bridge located in Bihar, spanning the Ganges River, and is not related to the River Hugli in Kolkata.
In conclusion, the correct answer is (D) Only (A) & (B), as both the Howrah Bridge and the Vidyasagar Setu are built on the River Hugli in Kolkata. Understanding the geography and infrastructure of Kolkata is crucial for comprehending the city's development and the role of these bridges in its urban landscape.